BB has his own style. I wouldn't say its any more or less real, just different. It's closer to jazz than the other guys you mentioned. There was a time in the 70's - 80's when he dipped more into soul than I cared to listen to. I've only seen him live once - I think it was 1981 - and he had just about a whole orchestra backing him up, including sythesizers, which I felt was terribly excessive - but he still sent a chill up my spine when he sang the line "tell that slick insurance salesman, he'd better write some insurance for himself." He was introduced as "the great gentleman of the blues" which really sums it up. Lately when I've seen him on TV he has gone more back to his roots with a smaller band and more traditional blues songs. His sound is different (some would say more refined) than Muddy, Wolf, etc. because he uses a hollow-body guitar which doesn't have much sustain, and as far as I know he never uses a slide. Also he doesn't play rhythm much, just the lead fills and solos.